As you develop your movie project in iMovie, you’ll find that you need more control over the clips in the movie timeline. iMovie has advanced editing tools that enable you to precisely control the duration and orientation of the clip and to correct problems with the recorded video. You can quickly delete or rotate clips in the timeline and split a movie clip into two clips. iMovie can also correct shaky or blurry video caused by the camera being moved too quickly when recording the video.

Trimming Movie Clips

When you adjust the starting and ending frames of the movie clips in the timeline, you are trimming a clip. iMovie lets you zero in on a frame-by-frame view of your video so that you can precisely set your starting and ending frames for each clip in the movie timeline.

When you select a clip in the timeline, iMovie displays a skimmer and a playhead for previewing and playing the video. Use the skimmer to preview your clips frame-by-frame, and then set the exact starting and ending frames for your clip and trim the clip. iMovie has a few different ways to trim a clip. One way is to trim the clip directly in the movie timeline.

Trimming a Clip in the Timeline Doesn’t Affect Linked Clip in Event

When you add a clip to the timeline, it maintains a link to the original clip that is grouped in an event in the Library list. Any trimming of the video is only to the clip in the movie timeline; the original video is still intact where it is stored on your computer. If you want to trim the original video, you need to do this on the recording device where the video was first recorded.

Add a clip from the Event Browser to the movie timeline by double-clicking a clip to select it in the Event Browser, and then dragging it into the movie timeline.

Move your mouse pointer anywhere in the selected clip and the skimmer displays. Move your mouse pointer left or right (don’t click and drag) to skim through the video. The Viewer displays the video as you skim through the video of the clip.

Using the Arrow Keys to Skim Through a Clip

Click to set the playhead at a specific location in the selected clip. Then press the left- or right-arrow keys on your keyboard to advance one frame at a time through the video.

To adjust the starting or ending frame of the movie, position the mouse pointer on the left or right border of the clip. The pointer becomes the Trim tool, as indicated by the double-headed arrow. Click and drag to the left or right to adjust the starting or ending frame of the clip. A time adjustment displays indicating the amount of time you are deleting or adding.

Adjusting the Clip Display Size for More Precise Trimming

Use the Zoom In or Out on Clips slider in the Project Browser to increase the view of the clip you are trimming for more precise edits to the video in a clip.

To adjust what video is shown in the trimmed clip, move your mouse to the center of the trimmed clip, then click and drag left or right to reposition the clip’s video to the new duration created by the starting and ending frames. Your pointer turns to a double-arrow filmstrip tool.

When you have the clip trimmed as you want, close the Clip Trimmer by clicking the Close Clip Trimmer button.

Use the Precision Editor

iMovie also has the Precision Editor for making frame-by-frame edits to a clip to set a precise duration of the video for the clip. It is similar to the Clip Trimmer as it lets you fine-tune the starting and ending frames of your movie but with even more precision as you can overlap the outgoing clip with the incoming clip for a nice transition between clips. It also lets you adjust the starting and ending frames of a transition between clips.

Double-click either the left or right border of a clip in the timeline. The Precision Editor opens. Based on whether you choose the first clip or a clip in the middle of the movie timeline, the Precision Editor displays a little differently:

Display of any clip other than the first clip in the movie timeline opened in the Precision Editor. In the figure, the Precision Editor displays the starting frame of the incoming clip and the ending frame of the outgoing clip in the movie project.

Even though the display is a little different based on what clip you are editing, the tools of the Precision Editor work the same. To edit the starting or ending frames of a clip, click and drag the left or right border of the active clip in the Precision Editor.

Another way to lengthen or shorten a clip in the Precision Editor is to click and drag from the center of the clip, left or right. The entire clip moves and the clip is either shortened or lengthened in its duration based on the direction you drag. You need to adjust the transition duration as it becomes longer, as you make the clip duration shorter; conversely, the transition becomes shorter as you make the clip longer in duration.

To modify the transition starting and ending frames in both the incoming and outgoing clip, click the Starting/Ending Frame button in the middle of the Transition Adjustment tool and drag left or right. The incoming and the outgoing transition lengthen or shorten based on the direction you drag.

You can also adjust the audio track of the incoming and outgoing clips so that the audio ends or begins where you want it or overlaps between the two clips. Make sure you have your audio waveforms displayed by choosing View, Show Waveforms.

To adjust the audio starting and ending frames, position your mouse pointer on the audio edit point in the audio waveform, the pointer becomes the double-headed arrow. Click and drag the audio edit point left or right for either the incoming or outgoing clip.